1. Field of the Invention
This invention relates to apparatus to be used for removing and replacing a preloaded helical coil spring which is part of a shock absorber, and more particularly to apparatus for readily compressing the spring.
2. Description of the Prior Art
Shock absorbers of the type characteristically used on motorcycles employ a hydraulic cylinder surrounded at least for a portion of its length by a coil spring maintained in a compressed state between a pair of keepers. One of the keepers is integral with the outer casing of the hydraulic cylinder and the other keeper is removably located on or affixed to the piston rod extending from the hydraulic cylinder. The removability of the keeper permits facile changing of the coil spring to thus alter the characteristics of the shock absorber depending on the spring rate.
In motorcycle racing, it is desired to frequently and rapidly change a shock absorber spring in repairing or rebuilding a shock absorber or to change load ratings on a shock absorber to adjust to or accommodate race course surface variations. Usually these changes must be made quickly, between racing heats and not always under ideal working conditions. The combined efforts of several persons is needed to compress the coil spring and remove the keeper, and then, after a replacement spring has been installed, to compress the spring and reassemble the keeper. There exists a need for a simple, easily handled apparatus to enable one person under stressful, somewhat improvised conditions to quickly and handily change a shock absorber spring.
In the prior art, Smyser U.S. Pat. No. 3,278,157 discloses a type of shock absorber spring compressor which requires the installation and then the removal of a lock bolt and nut through the spring. Castoe U.S. Pat. No. 3,814,382 discloses a type of spring compressor which requires a yoke pusher plate and cooperating bracket as well as a power source. Neither patent teaches a shock absorber remover which has the versatility and relative simplicity of operation or affords the speedy removal of a spring as provided by this invention.